Are you having difficulties incorporating OPC data into your Visual FoxPro solution? Need to create an OPC FoxPro program quickly and in quality? If so, QuickOPC comes to the rescue. Fox programs can now connect to OPC servers with ease.
QuickOPC is a set of components that simplify the task of integrating OPC client functionality into applications. Reading a value from OPC Data Access or OPC Unified Architecture (OPC UA) server, or writing a data value can be achieved in just one or two lines of code!
QuickOPC is a radically new approach to access OPC data. Traditionally, OPC programming required complicated code, no matter whether you use OPC custom or automation interfaces. OPC Server objects must be instantiated, OPC Group objects must be created and manipulated, OPC Items must be added and managed properly, and subscriptions must be established and maintained. Too many lines of error-prone code must be written to achieve a simple goal – reading or writing a value. QuickOPC saves you all that hassle.
QuickOPC can also connect to OPC UA (Universal Architecture) servers.
QuickOPC is unbelievably easy to use - here is a Visual FoxPro example which reads and displays OPC data from a common OPC server:
PROCEDURE Click oClient = CREATEOBJECT("OPCLabs.EasyOpc.DataAccess.EasyDAClient") MESSAGEBOX(oClient.ReadItemValue("", "OPCLabs.KitServer.2", "Simulation.Random")) ENDPROC
Or, using OPC-UA (Unified Architecture):
PROCEDURE Click oClient = CREATEOBJECT("OpcLabs.EasyOpc.UA.EasyUAClient") MESSAGEBOX(oClient.ReadValue( "opc.tcp://opcua.demo-this.com:51210/UA/SampleServer", "nsu=http://test.org/UA/Data/;i=10853")) ENDPROC
Do you think it can be any simpler? But the simplicity of the resulting Fox code is not the only advantage; the component is also very powerful. Using complex heuristic algorithms to optimize itself on the fly, it provides the most efficient, fastest access to the OPC data.
The PubSub variety of OPC UA (as opposed to client-server) uses message-oriented middleware to deliver the data. QuickOPC supports it as well. Code example is available in the documentation, and installed with the product.
Useful links: Examples / Knowledge Base
Footnote & required disclosure: QuickOPC (including its Options) is a software development kit (SDK) for development of OPC clients. Installing QuickOPC or its Options does not change system settings.